#Question id: 10362
#Unit 6. System Physiology – Plant
Bacteria can convert atmospheric nitrogen into ammonia,
Several form symbiotic associations with higher plants is given below;
HOST PLANT
N-FIXING SYMBIONTS
A)
Gunnera
i) Frankia
B) Azolla
ii)
Acetobacter
C)
Leguminous
iii) Azospirillum
D) Actinorhizal
iv) Nostoc
E) Sugarcane
v) Anabaena
F) Miscanthus vi) Sinorhizobium
Which of the following combination with the host plants and
n-fixing symbionts is CORRECT?
#Question id: 10363
#Unit 6. System Physiology – Plant
Free living nitrogen fixing takes place as shown in the following;
TYPE
N-FIXING GENERA
A)
Cyanobacteria (blue-green algae) i)
Bacillus
B)
Aerobic
ii)
Clostridium
C)
Facultative
iii) Anabaena
D)
Anaerobic nonphotosynthetic iv)
Rhodospirillum
E)
Anaerobic photosynthetic
v) Azospirillum
#Question id: 10365
#Unit 6. System Physiology – Plant
Why the nitrogenase enzymes catalyzes the nitrogen fixation reaction only in microanaerobic or anaerobic conditions?
#Question id: 10366
#Unit 6. System Physiology – Plant
Cyanobacteria can fixes nitrogen in an anaerobic conditions. Which of the following statements about heterocyst which is specialized cell of blue-green algae is incorrect?
#Question id: 10367
#Unit 6. System Physiology – Plant
Cyanobcteria also fixes nitrogen under anaerobic conditions without heterocyst where?
#Question id: 10368
#Unit 6. System Physiology – Plant
Free-living bacteria that are capable of fixing nitrogen are aerobic, facultative, or anaerobic. Some of the Aerobic nitrogen-fixing bacteria such as